The present invention relates generally to the art of tire changing machines. More particularly, the present invention relates to a tire changing machine incorporating an oil injection system.
Those of skill in the art of designing and manufacturing equipment used to change tires mounted on the rims of cars, light trucks, and other vehicles will appreciate that many prior art tire changing machines exist. For example, a rim holding tire changer is disclosed in U.S. Pat. No. 6,182,736 to Cunningham et al., the disclosure of which is incorporated herein by reference.
Many tire changers include pneumatic systems for the operation of various mechanisms. Among these mechanisms are bead breakers, assist arms and other features utilized in the tire changing operation. Flat turntables on which the tire is mounted for rotation are often turned by pneumatic motors located inside the base of the tire changer. In addition, radial clamps are usually provided on the turntable, which are themselves powered by pneumatics. The tire changer may also include an air hose for inflation of the tire after mounting.
As one skilled in the art will appreciate, it is necessary to lubricate the various pneumatically-powered mechanisms provided on such a tire changer. In order to achieve self lubrication, many such tire changers have been equipped with a “filter-lube.” The filter-lube is a device mounted to the tire changer through which the compressed air passes before being fed to various internal components. The filter-lube includes a pair of small reservoirs, one of which contains the lubricating oil. As the air passes through the oil reservoir, some of the lubricating oil is entrained in the air. The second reservoir collects water that is removed from the air as it passes through the filter-lube.
While the filter-lube works generally well, it does have several drawbacks. In a tire changer utilizing a filter-lube, for example, all compressed air is lubricated regardless of the need. This includes compressed air utilized for tire inflation. In addition, the oil reservoir of a filter-lube is relatively small. As a result, the supply of oil in the reservoir must be replenished on a frequent basis.